Gasoline stored in a fuel tank of a motorcycle is evaporated into a gasoline vapor. To reuse the gasoline vapor without releasing it to outside air, the motorcycle includes a canister placed below a seat. With an increase in functions incorporated into the motorcycle, the number of devices other than the canister, which are placed below the seat, tends to be increased, and a space below the seat in which the canister is placed tends to be reduced. Under these circumstances, the canister may be placed in a space other than the space below the seat. As an example of this, a fuel vapor treatment device disclosed in Patent Literature 1 is known. In the fuel vapor treatment device of Patent Literature 1, the canister is placed in a recess formed by a protruding portion, which is provided between a head light and a fuel tank and inward relative to an upper front side cowling.